A company called Lodsys claims to own four patents covering the in-app purchase mechanism found on iOS devices, and is seeking licensing fees from at least five individual developers, the Guardian reports. Some developers have received hand-delivered documents threatening patent infringement lawsuits if they don't pay up.

"They seem to be effectively claiming the rights to in-app purchase, but going after me, not Apple," James Thomson, developer of PCalc, wrote on Twitter. Thomson has alluded to Lodsys' involvement but not confirmed it outright. Other developers confirmed Lodsys' involvement to the Guardian and MacRumors.

It's not clear whether Apple has already licensed the relevant patents. The Website of Dan Abelow, who invents patents and uses Lodsys to license them, lists Apple as a licensee, but he told the Guardian that he doesn't know which companies licensed the patents in this particular case.

If Apple has a license for the relevant patents, the threats to developers is a simple cash grab. If not, Lodsys' decision to go after small developers is likely a bullying tactic intended to gain settlements from developers who can't afford a lawsuit. These settlements could then be used by Lodsys as ammunition against Apple.

In any case, Apple will probably want to get involved sooner than later. Not only could early settlements by app developers come back to haunt Apple in a future lawsuit, it could also make the App Store seem less hospitable to small-scale programmers, who are increasingly relying on "freemium" business models. Thomson said on Twitter that he's reached out to Apple's legal department for guidance, but there's no official word from Apple on the matter.

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